Improvement in friction driving-gears



W. W. TUNIS.

Friction Driving-Gear.

NO. 134,825. Patentedlan.14,1873.

Ewen/Ibn 'Nrrn Sra'rns I IMPROVEMENT IN FRICTION DRIVING=GEARS.

Specification forming part of Letters Patent No. 134,@25, dated January 14, 18'. 3.

To all whom 'it may concern:

Be it known that I, WILLIAM W. TUNIS, of Easton, in the county of Talbot and State of Maryland,have invented certain new and useful Improvement in Friction Driving Gear; and

I do hereby declare the following to be afull, clear, and exact description, of the same, reference being had to the accompanyin gdrawin g making part of this specification, in which- Figure l representsthe driving-gear in perspective, and Fig. 2 represents a top plan of the same.

I am aware that several kinds of frictional driving-gears have been essayed, and among them those that have been arranged for varying the speed of the operatin g shaft, but so far as I know and believe they have not gone into general use because of difficulties or defects, which I have obviated in my construction of such gearing. My invention consists in the construction and arrangement of a pair of disks, one upon a driving and the other upon a driven shaft, and at any desirable distance apart, and betweenithem two pairs of beveledged friction-wheels, each pair arranged upon 011e shaft and upon 'one or opposite sides of the disks, and the shafts arranged in hinged or swinging-frames, operated by a lever or its substitute to bring said bevel-edged wheels with equal force against the opposite sides of said disks, and mounting said pairs of frictionwheels upon, or in a longitudinally sliding bed or frame, so that they may be shifted to and from the centers of the driving and driven disks to change the speed of the driven shaft at pleasure.

To enable others skilled in the art to make and use my invention, I will proceed to describe the same with reference to the drawing.

On a bed or base, A, of any suitable kind, are arranged pillars or bearings B, in which a shaft, c, is supported, so that it may freely turn therein, but prevented by shoulders or collars from having any longitudinal play. Upon this shaft cis arranged the crank or band-wheel D by which it is driven. Gentrally and permanently arranged upon this shaft c there is a disk, E, which may be of such diameter as the special kind of machinery to be driven may require. Upon the bed or base A, or elsewhere, are arranged two other bearings or pillars, I?, in which a shaft, G, is supported, which shaft carries a second disk, H, that turns with said shaft.

I have shown the disks and their shafts as being parallel and in the same planes with each other. This is not, however imperative, asin most kinds of frictonal gearing, for I can arrange said shafts and disks at an oblique angle to each other, and so carry thepower in an angular or oblique direction, aswell as in a right line, and thus select the location or position of the driving and the driven mechanism, which is sometimes quite important.

Between the disks E H and their shafts C G, I arrange two pairs, a a and b Z1', ot' beveledged friction-wheels, one pair to bear against one of the faces or sides of each of the disks E H, and the other pair against the opposite sides, so that when brought tight up against such sides of the disks the strain will be upon the disks and not upon their shafts, which latter would bend or strain the shafts, throw them out of true workin g-line and render the machine inoperative.v The friction-wheels a and a', and those b and I", `are arranged, as

above stated, upon opposite sides of the disksV E H, those a a upon a shaft, c, which extends from one to the other, and those b b upon a shaft, d, parallel to that, c, but upon opposite sides of the disks, as seen in the drawing. These shafts c and d are supported in bearings ef, respectively, which bearings are hinged, as at g, to or on a sliding plate or frame, I, so that said friction-wheels in pairs maynot only be swung to or from the disks to put them into or out of driving action, but may also be moved longitudinally so that one wheel of each pair shall be further from, and the other one of said pair nearer to, the center ot' motion of their' respective disks, and so correspondingly change the speed of the disks. 'lheV hinged bearings g I have represented as connected together by a piece, h, extending from one to the other 5 and in upright pieces j attached thereto is a screw-shaft, i, to one end of which a winch or wrench, 7c, is affixed, so that each pair of friction-wheels may be simultaneously, and with uniform pressure, brought up against their respective sides of the disks, and as simultaneously released from frictional contact therewith, a coiled spring around said screw-shaft, and bearing against shafts c d centrally between their supports.

This, when the shafts are short and the disks are close together, will answer, but when the shafts are long pressure so applied would spring them and make the parts inoperative. When the disks are at remote distances and the shafts carrying the friction-wheels are correspondingly long, then the bearings g may not be united by the bar h, but separate from each other, and the friction-wheels thrown up by cams or levers arranged near each one of the pairs, and thus not endanger the shafts by bending or springing them out of line. The sliding plate or frame I, together with the hinged supports, friction-wheels and their shafts, and appliances for operating them, are

moved by means ofa lever, J, pivoted atm to said plate or frame I, and its point restrained between studs n or other controlling stops.

Having thus fully described my invention,

sented.

WILLIAM W. TUNIS. Witnesses:

A. B. STOUGHTON, E. L. TUNIS. 

